Macrodiversity power control in hierarchical CDMA cellular systems

Hierarchical CDMA cellular systems, consisting of macrocells with underlying microcells, are studied. We apply a resource management scheme called hierarchical maximal ratio combining (HMRC), where each mobile station (MS) is decoded by base stations (BS) in both layers. We first derive simple analytical solutions for HMRC reverse link CIR performance under different hierarchical settings. Our analytical solutions are verified by extensive Monte-Carlo simulations and HMRC is proven to be effective in hierarchical settings. It is observed that both macrocell and microcell capacities are nearly unaffected by each other's presence when HMRC is employed.